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1.
Pediatr Cardiol ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519622

RESUMO

We sought to evaluate the potential clinical role of 4D-flow cardiac magnetic resonance (CMR)-derived energetics and flow parameters in a cohort of patients' post-Fontan palliation. In patients with Fontan circulation who underwent 4D-Flow CMR, streamlines distribution was evaluated, as well a 4D-flow CMR-derived energetics parameters as kinetic energy (KE) and energy loss (EL) normalized by volume. EL/KE index as a marker of flow efficiency was also calculated. Cardiopulmonary exercise test (CPET) was also performed in a subgroup of patients. The population study included 55 patients (mean age 22 ± 11 years). The analysis of the streamlines revealed a preferential distribution of the right superior vena cava flow for the right pulmonary artery (62.5 ± 35.4%) and a mild preferential flow for the left pulmonary artery (52.3 ± 40.6%) of the inferior vena cave-pulmonary arteries (IVC-PA) conduit. Patients with heart failure (HF) presented lower IVC/PA-conduit flow (0.75 ± 0.5 vs 1.3 ± 0.5 l/min/m2, p = 0.004) and a higher mean flow-jet angle of the IVC-PA conduit (39.2 ± 22.8 vs 15.2 ± 8.9, p < 0.001) than the remaining patients. EL/KE index correlates inversely with VO2/kg/min: R: - 0.45, p = 0.01 peak, minute ventilation (VE) R: - 0.466, p < 0.01, maximal voluntary ventilation: R:0.44, p = 0.001 and positively with the physiological dead space to the tidal volume ratio (VD/VT) peak: R: 0.58, p < 0.01. From our data, lower blood flow in IVC/PA conduit and eccentric flow was associated with HF whereas higher EL/KE index was associated with reduced functional capacity and impaired lung function. Larger studies are needed to confirm our results and to further improve the prognostic role of the 4D-Flow CMR in this challenging population.

2.
Cell Mol Neurobiol ; 44(1): 21, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349562

RESUMO

It is well known that as part of their response to infectious agents such as viruses, microglia transition from a quiescent state to an activated state that includes proinflammatory and anti-inflammatory phases; this behavior has been described through in vitro studies. However, recent in vivo studies on the function of microglia have questioned the two-phase paradigm; therefore, a change in the frequency of in vitro studies is expected. A systematic review was carried out to identify the microglial cytokine profile against viral infection that has been further evaluated through in vitro studies (pro-inflammatory or anti-inflammatory), along with analysis of its publication frequency over the years. For this review, 531 articles published in the English language were collected from PubMed, Web of Science, EBSCO and ResearchGate. Only 27 papers met the inclusion criteria for this systematic review. In total, 19 cytokines were evaluated in these studies, most of which are proinflammatory; the most common are IL-6, followed by TNF-α and IL-1ß. It should be pointed out that half of the studies were published between 2015 and 2022 (raw data available in https://github.com/dadriba05/SystematicReview.git ). In this review, we identified that evaluation of pro-inflammatory cytokines released by microglia against viral infections has been performed more frequently than that of anti-inflammatory cytokines; additionally, a higher frequency of evaluation of the response of microglia cells to viral infection through in vitro studies from 2015 and beyond was noted.


Assuntos
Citocinas , Viroses , Humanos , Microglia , Fator de Necrose Tumoral alfa , Anti-Inflamatórios
5.
Arch Med Res ; 54(5): 102843, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37429750

RESUMO

BACKGROUND: Clinically Isolated Syndrome (CIS) is the first clinical episode suggestive of Clinical Definite Multiple Sclerosis (CDMS). There are no reports on possible predictors of conversion to CDMS in Mexican mestizo patients. AIM OF THE STUDY: To investigate immunological markers, clinical and paraclinical findings, and the presence of herpesvirus DNA to predict the transition from CIS to CDMS in Mexican patients. METHODS: A single-center prospective cohort study was conducted with newly diagnosed patients with CIS in Mexico between 2006 and 2010. Clinical information, immunophenotype, serum cytokines, anti-myelin protein immunoglobulins, and herpes viral DNA were determined at the time of diagnosis. RESULTS: 273 patients diagnosed with CIS met the enrolment criteria; after 10 years of follow-up, 46% met the 2010 McDonald criteria for CDMS. Baseline parameters associated with conversion to CDMS were motor symptoms, multifocal syndromes, and alterations of somatosensory evoked potentials. The presence of at least one lesion on magnetic resonance imaging was the main factor associated with an increased risk of conversion to CDMS (RR 15.52, 95% CI 3.96-60.79, p = 0.000). Patients who converted to CDMS showed a significantly lower percentage of circulating regulatory T cells, cytotoxic T cells, and B cells, and the conversion to CDMS was associated with the presence of varicella-zoster virus and herpes simplex virus 1 DNA in cerebrospinal fluid and blood. CONCLUSION: There is scarce evidence in Mexico regarding the demographic and clinical aspects of CIS and CDMS. This study shows several predictors of conversion to CDMS to be considered in Mexican patients with CIS.


Assuntos
Doenças Desmielinizantes , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico , Estudos Prospectivos , México/epidemiologia , Progressão da Doença , Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/patologia , Imageamento por Ressonância Magnética/métodos
6.
J Cardiovasc Magn Reson ; 25(1): 40, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474977

RESUMO

Hemodynamic assessment is an integral part of the diagnosis and management of cardiovascular disease. Four-dimensional cardiovascular magnetic resonance flow imaging (4D Flow CMR) allows comprehensive and accurate assessment of flow in a single acquisition. This consensus paper is an update from the 2015 '4D Flow CMR Consensus Statement'. We elaborate on 4D Flow CMR sequence options and imaging considerations. The document aims to assist centers starting out with 4D Flow CMR of the heart and great vessels with advice on acquisition parameters, post-processing workflows and integration into clinical practice. Furthermore, we define minimum quality assurance and validation standards for clinical centers. We also address the challenges faced in quality assurance and validation in the research setting. We also include a checklist for recommended publication standards, specifically for 4D Flow CMR. Finally, we discuss the current limitations and the future of 4D Flow CMR. This updated consensus paper will further facilitate widespread adoption of 4D Flow CMR in the clinical workflow across the globe and aid consistently high-quality publication standards.


Assuntos
Sistema Cardiovascular , Humanos , Velocidade do Fluxo Sanguíneo , Valor Preditivo dos Testes , Coração , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
11.
J Cardiovasc Transl Res ; 16(4): 862-873, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36745287

RESUMO

Aortic stenosis is a condition which is fatal if left untreated. Novel quantitative imaging techniques which better characterise transvalvular pressure drops are being developed but require refinement and validation. A customisable and cost-effective workbench valve phantom circuit capable of replicating valve mechanics and pathology was created. The reproducibility and relationship of differing haemodynamic metrics were assessed from ground truth pressure data alongside imaging compatibility. The phantom met the requirements to capture ground truth pressure data alongside ultrasound and magnetic resonance image compatibility. The reproducibility was successfully tested. The robustness of three different pressure drop metrics was assessed: whilst the peak and net pressure drops provide a robust assessment of the stenotic burden in our phantom, the peak-to-peak pressure drop is a metric that is confounded by non-valvular factors such as wave reflection. The peak-to-peak pressure drop is a metric that should be reconsidered in clinical practice. The left panel shows manufacture of low cost, functional valves. The central section demonstrates circuit layout, representative MRI and US images alongside gross valve morphologies. The right panel shows the different pressure drop metrics that were assessed for reproducibility.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Humanos , Reprodutibilidade dos Testes , Benchmarking , Hemodinâmica
13.
Gac Med Mex ; 158(5): 332-334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36572021

RESUMO

Lawsuits due to patient perception of inappropriate medical actions are a growing reality in medical practice, which entails widespread concern in the medical community. Lawsuits often entail additional circumstances beyond the primary concern of preventing or sanctioning acts of medical negligence. CETREMI proposes various recommendations aimed at legal and medical professionals to improve this circumstance and avoid harming the doctor-patient relationship.


Las demandas judiciales por la percepción del paciente de una actuación médica inadecuada son una realidad creciente en la práctica médica, la cual entraña una preocupación extendida en el gremio médico. Las demandas judiciales frecuentemente conllevan circunstancias adicionales a la primaria preocupación de prevenir o sancionar actos de negligencia médica. CETREMI emite algunas recomendaciones a los profesionales jurídicos y médicos para mejorar esta situación y evitar daños en la relación médico-paciente.


Assuntos
Imperícia , Relações Médico-Paciente , Humanos
14.
Gac. méd. Méx ; 158(5): 343-345, sep.-oct. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1404865

RESUMO

Resumen Las demandas judiciales por la percepción del paciente de una actuación médica inadecuada son una realidad creciente en la práctica médica, la cual entraña una preocupación extendida en el gremio médico. Las demandas judiciales frecuentemente conllevan circunstancias adicionales a la primaria preocupación de prevenir o sancionar actos de negligencia médica. CETREMI emite algunas recomendaciones a los profesionales jurídicos y médicos para mejorar esta situación y evitar daños en la relación médico-paciente.


Abstract Lawsuits due to patient perception of inappropriate medical actions are a growing reality in medical practice, which entails widespread concern in the medical community. Lawsuits often entail additional circumstances beyond the primary concern of preventing or sanctioning acts of medical negligence. CETREMI proposes various recommendations aimed at legal and medical professionals to improve this circumstance and avoid harming the doctor-patient relationship.

15.
Gac Med Mex ; 158(3): 157-159, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35894750

RESUMO

Due to sanitary restrictions secondary to the COVID-19 pandemic, various interactions between the pharmaceutical industry and physicians have changed. One of them has been the method for promoting medicinal products through academic meetings around diseases of financial interest. A recent modality has been unilateral promotion by the pharmaceutical industry through academic events with the invitation of so-called "experts" for the promotion of a specific drug. These meetings are often biased not towards optimal care of a disease, but rather towards commercial promotion of a specific drug, which may or may not be the best option, without considering associated therapeutic alternatives. The Committee of Ethics and Transparency in the Physician-Industry Relationship, of the National Academy of Medicine, analyzes this new circumstance and proposes some considerations to the medical community.


Debido a las restricciones sanitarias secundarias a la pandemia de COVID-19, diversas interacciones entre la industria farmacéutica y los médicos cambiaron. Una de ellas ha sido el método promocional de medicamentos a través de reuniones académicas en torno a padecimientos de interés financiero. Una modalidad reciente ha sido la promoción unilateral de un fármaco determinado por parte de la industria farmacéutica por medio de eventos académicos con la invitación de aparentes "expertos". Estas reuniones frecuentemente están sesgadas no hacia la atención óptima de un padecimiento, sino a la promoción comercial de un medicamento específico que pudiera o no ser la mejor opción o sin la consideración de alternativas terapéuticas asociadas. El Comité de Ética y Transparencia en la Relación Médico-Industria, de la Academia Nacional de Medicina de México, analiza esta nueva circunstancia y propone algunas consideraciones a la comunidad médica.


Assuntos
COVID-19 , Medicina , Médicos , Indústria Farmacêutica , Humanos , Pandemias
16.
Front Cardiovasc Med ; 9: 885338, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35665243

RESUMO

Background and Purpose: Prognostic models based on cardiovascular hemodynamic parameters may bring new information for an early assessment of patients with bicuspid aortic valve (BAV), playing a key role in reducing the long-term risk of cardiovascular events. This work quantifies several three-dimensional hemodynamic parameters in different patients with BAV and ranks their relationships with aortic diameter. Materials and Methods: Using 4D-flow CMR data of 74 patients with BAV (49 right-left and 25 right-non-coronary) and 48 healthy volunteers, aortic 3D maps of seventeen 17 different hemodynamic parameters were quantified along the thoracic aorta. Patients with BAV were divided into two morphotype categories, BAV-Non-AAoD (where we include 18 non-dilated patients and 7 root-dilated patients) and BAV-AAoD (where we include the 49 patients with dilatation of the ascending aorta). Differences between volunteers and patients were evaluated using MANOVA with Pillai's trace statistic, Mann-Whitney U test, ROC curves, and minimum redundancy maximum relevance algorithm. Spearman's correlation was used to correlate the dilation with each hemodynamic parameter. Results: The flow eccentricity, backward velocity, velocity angle, regurgitation fraction, circumferential wall shear stress, axial vorticity, and axial circulation allowed to discriminate between volunteers and patients with BAV, even in the absence of dilation. In patients with BAV, the diameter presented a strong correlation (> |+/-0.7|) with the forward velocity and velocity angle, and a good correlation (> |+/-0.5|) with regurgitation fraction, wall shear stress, wall shear stress axial, and vorticity, also for morphotypes and phenotypes, some of them are correlated with the diameter. The velocity angle proved to be an excellent biomarker in the differentiation between volunteers and patients with BAV, BAV morphotypes, and BAV phenotypes, with an area under the curve bigger than 0.90, and higher predictor important scores. Conclusions: Through the application of a novel 3D quantification method, hemodynamic parameters related to flow direction, such as flow eccentricity, velocity angle, and regurgitation fraction, presented the best relationships with a local diameter and effectively differentiated patients with BAV from healthy volunteers.

17.
Gac. méd. Méx ; 158(3): 167-169, may.-jun. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1404833

RESUMO

Resumen Debido a las restricciones sanitarias secundarias a la pandemia de COVID-19, diversas interacciones entre la industria farmacéutica y los médicos cambiaron. Una de ellas ha sido el método promocional de medicamentos a través de reuniones académicas en torno a padecimientos de interés financiero. Una modalidad reciente ha sido la promoción unilateral de un fármaco determinado por parte de la industria farmacéutica por medio de eventos académicos con la invitación de aparentes "expertos". Estas reuniones frecuentemente están sesgadas no hacia la atención óptima de un padecimiento, sino a la promoción comercial de un medicamento específico que pudiera o no ser la mejor opción o sin la consideración de alternativas terapéuticas asociadas. El Comité de Ética y Transparencia en la Relación Médico-Industria, de la Academia Nacional de Medicina de México, analiza esta nueva circunstancia y propone algunas consideraciones a la comunidad médica.


Abstract Due to sanitary restrictions secondary to the COVID-19 pandemic, various interactions between the pharmaceutical industry and physicians have changed. One of them has been the method for promoting medicinal products through academic meetings around diseases of financial interest. A recent modality has been unilateral promotion by the pharmaceutical industry through academic events with the invitation of so-called "experts" for the promotion of a specific drug; these meetings are often biased not towards optimal care of a disease, but rather towards commercial promotion of a specific drug, which may or may not be the best option, without considering associated therapeutic alternatives. The Committee of Ethics and Transparency in the Physician-Industry Relationship, of the National Academy of Medicine, analyzes this new circumstance and proposes some considerations to the medical community.

18.
Mater Today Bio ; 14: 100252, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35509864

RESUMO

Three-dimensional (3D) engineered cardiovascular tissues have shown great promise to replace damaged structures. Specifically, tissue engineering vascular grafts (TEVG) have the potential to replace biological and synthetic grafts. We aimed to design an in-vitro patient-specific patch based on a hybrid 3D print combined with vascular smooth muscle cells (VSMC) differentiation. Based on the medical images of a 2 months-old girl with aortic arch hypoplasia and using computational modelling, we evaluated the most hemodynamically efficient aortic patch surgical repair. Using the designed 3D patch geometry, the scaffold was printed using a hybrid fused deposition modelling (FDM) and electrospinning techniques. The scaffold was seeded with multipotent mesenchymal stem cells (MSC) for later maturation to derived VSMC (dVSMC). The graft showed adequate resistance to physiological aortic pressure (burst pressure 101 â€‹± â€‹15 â€‹mmHg) and a porosity gradient ranging from 80 to 10 â€‹µm allowing cells to infiltrate through the entire thickness of the patch. The bio-scaffolds showed good cell viability at days 4 and 12 and adequate functional vasoactive response to endothelin-1. In summary, we have shown that our method of generating patient-specific patch shows adequate hemodynamic profile, mechanical properties, dVSMC infiltration, viability and functionality. This innovative 3D biotechnology has the potential for broad application in regenerative medicine and potentially in heart disease prevention.

19.
Int J Numer Method Biomed Eng ; 38(6): e3603, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35434919

RESUMO

4D Flow Magnetic Resonance Imaging (MRI) is the state-of-the-art technique to comprehensively measure the complex spatio-temporal and multidirectional patterns of blood flow. However, it is subject to artifacts such as noise and aliasing, which due to the 3D and dynamic structure is difficult to detect in clinical practice. In this work, a new mathematical and computational model to determine the quality of 4D Flow MRI is presented. The model is derived by assuming the true velocity satisfies the incompressible Navier-Stokes equations and that can be decomposed by the measurements u→meas plus an extra field w→ . Therefore, a non-linear problem with w→ as unknown arises, which serves as a measure of data quality. A stabilized finite element formulation tailored to this problem is proposed and analyzed. Then, extensive numerical examples-using synthetic 4D Flow MRI data as well as real measurements on experimental phantom and subjects-illustrate the ability to use w→ for assessing the quality of 4D Flow MRI measurements over space and time.


Assuntos
Hemodinâmica , Imageamento por Ressonância Magnética , Velocidade do Fluxo Sanguíneo/fisiologia , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas
20.
Pharmaceutics ; 14(2)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35214059

RESUMO

A glioblastoma is an aggressive form of a malignant glial-derived tumor with a poor prognosis despite multimodal therapy approaches. Lactate has a preponderant role in the tumor microenvironment, playing an immunoregulatory role as well as being a carbon source for tumor growth. Lactate homeostasis depends on the proper functioning of intracellular lactate regulation systems, such as transporters and enzymes involved in its synthesis and degradation, with evidence that an intracellular lactate overload generates metabolic stress on tumor cells and tumor cell death. We propose that the delivery of a lactate overload carried in nanoparticles, allowing the intracellular release of lactate, would compromise the survival of tumor cells. We synthesized and characterized silica and titania nanoparticles loaded with lactate to evaluate the cellular uptake, metabolic activity, pH modification, and cytotoxicity on C6 cells under normoxia and chemical hypoxia, and, finally, determined the survival of an orthotopic malignant glioma model after in situ administration. A dose-dependent reduction in metabolic activity of treated cells under normoxia was found, but not under hypoxia, independent of glucose concentration. Lactated-loaded silica nanoparticles were highly cytotoxic (58.1% of dead cells) and generated significant supernatant acidification. In vivo, lactate-loaded silica nanoparticles significantly increased the median survival time of malignant glioma-bearing rats (p = 0.005) when administered in situ. These findings indicate that lactate-loaded silica nanoparticles are cytotoxic on glioma cells in vitro and in vivo.

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